How are cosmic rays blocked?

Question

Matthew Arnold · Accepted Answer

Cosmic rays are blocked by certain materials if thick enough.

High energy atomic nuclei, of which high energy protons make up a significant portion and the most dangerous, are the source of cosmic rays. The Earth's atmosphere blocks the majority of cosmic rays, but other materials can also be used to block them. One particularly effective material is liquid water. Ironically, metal layers have the potential to exacerbate cosmic ray radiation because high energy protons can collide with metal nuclei and become unstable isotopes that decay radioactively. Studies have been conducted on the topic of shielding astronauts from cosmic radiation on a Mars mission. Materials such as water or even human waste have been proposed as potential barriers between the astronauts and the metal hull. Some alternatives to block protons include applying a positive electric charge to the spacecraft or using magnetic fields, both of which have drawbacks related to power consumption.

Anna Armstrong · Answer

undefined Cosmic rays are partially blocked by the Earth's atmosphere, primarily by the air molecules and magnetic fields in the atmosphere. Additionally, cosmic rays are also blocked by magnetic fields around planets and other celestial bodies in space.